package com.xy2401.example.util;

import java.math.BigInteger;
import java.util.Date;
import java.util.Random;
import java.util.Scanner;
import java.util.zip.CRC32;
    public class IdeaKeygen_14 {
      public static short getCRC(String s, int i, byte bytes[]){
          CRC32 crc32 = new CRC32();
          if (s != null)
          {
              for (int j = 0; j < s.length(); j++)
              {
                  char c = s.charAt(j);
                  crc32.update(c);
              }
          }
          crc32.update(i);
          crc32.update(i >> 8);
          crc32.update(i >> 16);
          crc32.update(i >> 24);
          for (int k = 0; k < bytes.length - 2; k++)
          {
              byte byte0 = bytes[k];
              crc32.update(byte0);
          }
          return (short) (int) crc32.getValue();
      }

      public static String encodeGroups(BigInteger biginteger){
          BigInteger beginner1 = BigInteger.valueOf(0x39aa400L);
          StringBuilder sb = new StringBuilder();
          for (int i = 0; biginteger.compareTo(BigInteger.ZERO) != 0; i++)
          {
              int j = biginteger.mod(beginner1).intValue();
              String s1 = encodeGroup(j);
              if (i > 0)
              {
                  sb.append("-");
              }
              sb.append(s1);
              biginteger = biginteger.divide(beginner1);
          }
          return sb.toString();
      }

      public static String encodeGroup(int i){
          StringBuilder sb = new StringBuilder();
          for (int j = 0; j < 5; j++)
          {
              int k = i % 36;
              char c;
              if (k < 10)
              {
                  c = (char) (48 + k);
              }
              else
              {
                  c = (char) ((65 + k) - 10);
              }
              sb.append(c);
              i /= 36;
          }
          return sb.toString();
      }

      public static String MakeKey(String name, int days, int id){
          id %= 100000;
          byte bkey[] = new byte[12];
          bkey[0] = (byte) 1; // Product type: IntelliJ IDEA is 1
          bkey[1] = 14; // version
          Date d = new Date();
          long ld = (d.getTime() >> 16);
          bkey[2] = (byte) (ld & 255);
          bkey[3] = (byte) ((ld >> 8) & 255);
          bkey[4] = (byte) ((ld >> 16) & 255);
          bkey[5] = (byte) ((ld >> 24) & 255);
          days &= 0xffff;
          bkey[6] = (byte) (days & 255);
          bkey[7] = (byte) ((days >> 8) & 255);
          bkey[8] = 105;
          bkey[9] = -59;
          bkey[10] = 0;
          bkey[11] = 0;
          int w = getCRC(name, id % 100000, bkey);
          bkey[10] = (byte) (w & 255);
          bkey[11] = (byte) ((w >> 8) & 255);
          BigInteger pow = new BigInteger("89126272330128007543578052027888001981", 10);
          BigInteger mod = new BigInteger("86f71688cdd2612ca117d1f54bdae029", 16);
          BigInteger k0 = new BigInteger(bkey);
          BigInteger k1 = k0.modPow(pow, mod);
          String s0 = Integer.toString(id);
          String sz = "0";
          while (s0.length() != 5)
          {
              s0 = sz.concat(s0);
          }
          s0 = s0.concat("-");
          String s1 = encodeGroups(k1);
          s0 = s0.concat(s1);
          return s0;
      }

      public static void main(String[] args){
          System.out.println("请输入用户名:");
          Scanner scanner = new Scanner(System.in);
          String username = scanner.next();
          Random r = new Random();
          System.out.println(MakeKey(username, 0, r.nextInt(100000)));
      }
    }